Annoyance response to mapped noise from combined road-traffic and railway system.

To study annoyance response to combined transportation noise from road-traffic and railway, a social survey has been performed in a highly populated residential area in the city of Seoul, South Korea. To determine the noise exposure level in an interviewed household, a noise mapping software package was utilized and the noise exposure level from each single source was calculated separately and combined to get total exposure level. The prediction was partially validated by measurements. The households in the study area are classified into acoustically differentiated groups which are named as the road-traffic noise dominant, railway noise dominant, and combined noise dominant, respectively. %HA (percentage of highly annoyed people) curves to noise exposure level are presented for the acoustically classified three groups. Comparison of the %HA curves shows that more people are highly annoyed to railway noise than road-traffic noise, but the curve for combined noise is much closer to the %HA curve for road-traffic noise rather than the %HA curve for railway noise. Multiple-regression and path analysis of the survey data give the direct and indirect quantitative relationships between annoyance and noise and non-noise factors. Personal sensitivity to noise and satisfaction of living environment are primary contributing factors.